Improvement in artificial leg and foot



"To all whom 'it may concern:

means by which it is secured to the leg.

Moses HQHAWKINSQOF NEW HAVEN. coNNncTICUT.

' Leners Patent No. 90,099, and May 18,1869.

MPRQVEMENT IN ARTIFICIAL LEG- AND FOOT -The Schedule referred to in these Lettera Patent and making part of the same.-

Bc it known that I, MOSES H. HAWKINS, of the city and county of New Haven, in the State of Connecticut,

" have invented a new and useful Improvement in Artifcial Leg and Foot 5 and I do hereby declare that the l following is afull, clear, and' eXact description of the construction, character, and operation of the same, reference being had to the accompanying drawings, which make part of thisspecification, in which,-

` 'Figure 2 is a perspective view of one et' the irons which support the journals of the pin, or arbor, on

which the `knee-joint vibrates, showing the dovetailform ofthe bearings. p p

Y Figure 3 is a perspective view of one ofthe journals v of the pin, or arbor, on which the joint vibrates. showing the leather case which surrounds it. ,4 Figure 4 is a vertical section, showlng the manner of connectingand adjusting theV ham-string, Svc.

Figure 5 is a perspective 'View of the joint ofthe i ankle, showing the mechanism for giving Vboth theA vertical and transverse motions to the foot, and the Figure-6 is aperspective View of the rear, or heelportion of the bottom of the foot, showing the screw which secures the foot to `the leg, and the twocords whichv govern the twoends, that is, the `heel and toe of the foot, and the mannerof adjusting them by the My improvements consist in covering or enveloping the fulcrum-pin of the knee'joint with leather, or any other suitable material, so as to obviate the ordinary friction; and in carrying the cord by an eye-splice, or

loop around a bar, fitted transversely in the leg, above the knee, with several notches in it to suit the desired Vthe two joints, knee and ankle, so that the foot may be held in the desired horizontal p position for its genl Veral eii'ect, but so `that thefoot `may bevibrated vertically, while walking; and in making the ham-string `readily!znljustable by means oi'` having, at rone end, an

eye-splice, o'r permanent loop, properly secured, and at the other end, an adjustable loop, to be secured by a suitable binding-plate, to securev the loop in any desired position, which the owner can readily do.

I make the upper part ofthe leg, or the part, above the knee, and containing the knee-joint, of wood, or any other suitable material, making it hollow, as represented at A, both l'oljglightness and convenience.

',lrausversely acrossthishollow part, I iit an' adj ustable bar, with anysuitable number of slots, or notches in it as represented at a a, iig. 1, to receive the loop,

or eye-splice, at one end, -bfof the cord B, while-the other end, as at c, is connected with the main spring C, of the leg, which. main spring is also connected with the foot-cords d and e.

I also lit the ham-stringD with a suitable loop, to

be secured by a suitable pin, or stay, as represented at j, iig. 1, and the upper loop or bight, f, I pass over a bearing, or stay, in theV upper part of the leg, in such a manner that a straight or fiat plate, f, may be applied i to bind it, by being secured, by screws, in the desired position to keep the knee-joint straight. In the knee, I support the journals of the joint-pin y, 1 andB, in slotted bearings, one of which is shown in fig. 2, and indicatedby dots at h, iig. l; and I connect the lower loop of the cord, which passes over it, with the main spring O, of the leg, so as to assist in working it, and also in working the ankle`joint, so that the action may be reciprocal.

I construct the ankle-joint substantially inthe manner represented in the double-jointed device shown in iig. 5, and indicated in section in fig. 1.

I make the ankle-joint fulcrum-pin with proper ,A journals, -as represented at l Z in iig. 5, and in section in tig. l, to regulate the verticahmotion of the foot, and with a rocker, as shown at m, g. 5, to admit of a lateral motion ofthe foot, the bar n of which rocker I extend'down through the solid part ofthe foot, and secure it by a nut, as indicated at n, figs. 1, 5, and 6, the bar being shown more fullying. 5.

I secure the fulcrum l l,of the ankle-joint, to the solid part G, of the ankle, by straps and` screws, as

represented at w, fig. 5, "and indicated in section in fig.` 1 and I t the rocker in a proper recess, as shown at m, iig. 5, to roll freely, so as toallow the foot to have a sutiiciently free lateral motion.

I t the cords (l and e to control the vertical motion of the-ioot, by attaching their upper ends to suitable hooks, as represented at p and g, fig. 1, connected with the main spring C, and extending them downward through holes in the lower portion of theankle and foot, where I loop each of them around, and secure `them firmly by binding-screws, as 'represented at c' The advantages ofmy improvement consist in'that by means of the bearings, as fig. 2, and indicated at h, fig. l, I secure the joint or fulcrum-pin g, of the knee-joint, and by holding this fulcrum-pin iixedly in ,its position, by means oi' thedovetail at y,'iig. 3, titting the dovetail slot, ,shown at IL, iig. 2, and using a loose leather `collar, or sheath, as represented at t, figs. l and 3, I entirely avoid friction on the kneecord B, as the leather ysheath always turns with the cord; and in that 1 can adjust the loop, at b, to either ofthe notches in the bara a, and I can also adjust the bar a a. by means of the adjusting-screw fv, I can give the proper tension to the knee-joint and in that by the means which I use for adjusting the ham-string around the stay f', and securing the loop in its position, by means of the metallic strap f, so as to enable the wearer to adjust it at any time, as before vdescribed; and in that the knee-cord B is connected with the main spring C, the whole can `be .tightened from above the knee, or under the fo'ot; andin that by my method of adjusting the cords d and e, by means of the binding-screws 1' and s, I can constantly keep the two joints, that is, the knee and ankle-joints, in

perfect order, and in the proper condition for use; and in that the adjustment may be made by the wearer, should he find it necessary, with the aid of a screw-driver, and perhaps a pair of pliers; and in that any dust which may accidentally penetrate into the leg, may fall out about the-bottom, as at y and f1', or pass down the holes for the cords d and e, so as never to injure the ankle-joint, as has often happened.

What I claim as my-invention, and desire to secure by Letters Patent, is- Y 1. The combination oi' the knee-cord B and the leather sheath t, with the main spring C, adjustable bar a @and fulerum-pin g, when constructed, arranged, and fitted4 substantially as herein described and set forth. 2. The combination of the cords d and e with the screws r and s, and the *main spring C, substantially as herein described and set forth.

3. The combination ofthe devices which constitute the double-acting ankle-joint, l l and m, fig. 5, substantially asl herein described and set forth.

M. H. HAWKINS.

Witnesses:

WM. D. CURTISS, R. FITZGERALD. 

